The 2013 Super Bowl was held in the middle of carnival. Fat Tuesday fell on Feb. 12 last year, just nine days after Super Bowl XLVII.

"The Super Bowl gave us a lot of great exposure around the country so the people who saw that happening last year, watching the game and seeing all the activity, probably put New Orleans on their bucket list for this year's travel," said Mark Romig, CEO of the New Orleans Tourism Marketing Corporation.

A 2011 study estimated Mardi Gras brings $144 million to the city in direct economic impact alone. It's a big boost to the 78,000 people who work in tourism and hospitality industries in the New Orleans metro.

"It started as a way to boost our economy back in the late 1800s," said Romig. "It's continued as this great driver of our cultural economy."

Romig expects the crowds this year to be as big, or bigger than last.

Crowds are expected to start rolling into town Friday night. Many hotels are near capacity.